Choice of suture technique 2
Objective 2. Appreciate the optimal use of sutures in ileocolic anastomoses
Size and spacing of the suture bites:
Greenall and colleagues performed a randomised controlled trial where patients were randomly allocated to have sutures placed either 5 or 10 mm from the cut edges of the bowel.
No significant differences in anastomotic leak were detected
Surgeons agreed that 3-5mm size ‘bites’ are adequate for handsewn anastomosis
but larger bites up to 10mm may be considered for diseased or thickened tissue.
Related paper: Influence of depth of suture bite on integrity of single-layer large-bowel anastomoses: controlled trial
Consensus also recommended that the size between bites reflected that of the size of the bite. For example, 3mm ‘bites’ should be placed 3mm apart, 5mm ‘bites’ should be placed 5mm apart, and so on. This is also reflected in animal studies.
Related paper: Influence of the distance between interrupted sutures and the tension of sutures on the healing of experimental colonic anastomoses
The video below shows surgeons discussing their choice of size and spacing of suture bites:
Choice of suture tension:
For the optimal anastomosis, a balance must be achieved between:
- Sutures be being tight enough to prevent dehiscence of the anastomosis
- Suture being loose enough to permit maximal perfusion of the cut edges.
The image on the right demonstrates anastomotic perfusion at varying suture tensions in an animal model.
Moderate tension gave the best histologic and microangiographic results.
Related paper: Influence of the Distance Between Interrupted Sutures and the Tension of Sutures on the Healing of Experimental Colonic Anastomoses
Configuration of the suture bite:
In animal models of bursting pressure at the anastomosis, mechanical strength of the intact intestinal wall was derived from the submucosa and muscularis, while the serosa and mucosa showed no significant strength.
Related paper: Participation of the intestinal layers in supplying of the mechanical strength of the intact and sutured gut
It is therefore essential that the submucosa and muscularis are included in the suture bite.
Choice of serosubmucosal or full-thickness suture bites:
Krasniqi and colleagues showed better histologic results for full-thickness sutures with equal anastomotic strength in a rat model
Related paper: A comparison of three single layer anastomotic techniques in the colon of the rat
Existing observational evidence from human data suggests that both serosubmucosal & full-thickness sutures are acceptable.
Related paper: The interrupted serosubmucosal anastomosis – still the gold standard
Related paper: Prospective audit of an extramucosal technique for intestinal anastomosis
Related paper: A single layer open anastomosis for all intestinal structures
Surgeons agreed that either seromuscular or full-thickness bites are acceptable.
Full thickness suture bites may be more secure in diseased tissue, where the anatomy is distorted
Choice of everted or inverted bowel edges:
In a randomised control trial Goligher and colleagues compared inverted and everted techniques for colorectal anastomosis. The everted suture anastomosis group had a substantially higher rate of faecal fistula (43%) than the inverted suture anastomosis group (8%).
No other recent prospective, randomised studies are available.
Surgeons agreed that inverting ileocolic anastomoses were preferable, ensuring the inclusion of the submucosa.
Related paper: A controlled trial of inverting versus everting intestinal suture in clinical large-bowel surgery